Septic arthritis due to <i>Corynebacterium propinquum</i> : first report of isolation from synovial fluid in a native joint

This case highlights the diagnostic value of using enrichment culture and comprehensive laboratory-clinical correlation to recognize clinically significant, low-virulence organisms, such as <i>Corynebacterium propinquum</i>. Accurate species-level identification and thoughtful interpretation within the clinical context are essential to distinguish contamination from true infection, particularly in sterile-site cultures associated with native joint infections.